Gatunek typowy
Polygnathus gyratilineatus Holmes, 1928 from the Gassaway Member of the Chattanooga Shale, Alabama.

Opis

Diagnosis. — Wide oval platform in P1 elements; M element preserves generalized polygnathid morphology.
Remarks. — There are some difficulties with delineating the boundary between early species of the ancyrognathid Polylophodonta and homeomorphic advanced platform-bering members of the Mehlina lineage (Polynodosus) if only platform elements are considered. 

Synonimy

Zasięg czasowy

Literatura

Dzik, J. 2006. The Famennian "Golden Age" of conodonts and ammonoids in the Polish part of the Variscan sea. Palaeontologia Polonica 63, 1-359.